Images of black-suited riot police firing tear gas and rounding up protesters on the streets and have cast a dramatic shadow over the Seattle meeting of the World Trade Organisation.

To make our city a place where all people live safely and without fear

Seattle Police Department mission statement

International media sent to cover the latest round of in a war of words over international trade found themselves instead covering a full-scale battle on the streets.

The Seattle Police Department (SPD) says it was caught off-guard by the protesters' actions and admits it failed to undertake an adequate "threat analysis" ahead of the gathering.

On reflection, said SPD Chief Ron Stamper, there were more violent protesters than "anybody could have predicted."

Warnings given

That there would be protests in Seattle was never a secret. Organisers had been openly planning to disrupt the World Trade Organisation's talks for the past nine months and had discussed their plans with police and city officials.

They insist they had given warnings that a hardcore of protesters would inevitably try to take
more direct, violent action.

"I made it very clear that there were lots of groups coming to Seattle, over which I wouldn't have any control" said Mike Dolan, one of the main protest organisers.

He says the police told him they were confident they could handle the protesters.

Change of plan

The police are having to do what they're having to do to ensure a safe environment

Mayor Paul Schell

The police's initial plans - later criticised as "timid" and "naive" - had been to stand alongside and contain the demonstrators, allowing them to make their point without actually disrupting the talks or causing any damage.

On Tuesday it quickly became apparent that that would not be enough.

Small groups of protesters broke off from the main march and set about laying into symbols of American corporate culture - Starbucks coffee shops, Gap clothing stores and Bank of America branches bore the brunt.

With government ministers blocked from leaving their hotels, forcing WTO officials to cancel the talks' opening ceremony, a change of tactics was needed.

Critics say police tactics were heavy-handed

Working in large groups, heavily armoured police tried to push the crowd away from the conference centre, dividing them into smaller pockets using pepper spray, tear gas and rubber bullets.

According to some local media reports, stun grenades were fired at the crowds without warning.

Critics say the police response was excessive and indiscriminate, targeting non-violent as well as violent protesters.

"It didn't make any sense" one protester told the Seattle Times. "They gassed us to move us back five or six feet."

"When this stuff was happening they didn't do anything," he said pointing to the broken shop fronts.

No protest zone

The violence is not with us, the violence is with the martial law that police have imposed on this city

Protester

Mayor Paul Schell, who had hoped the WTO meeting would prove an opportunity to showcase Seattle, imposed a curfew and 50-block "no protest zone" across the heart of the city.

The move was criticised by civil liberties groups who said the protest ban violated constitutional rights.

Nonetheless on Wednesday the protesters returned, determined to continue the battle for Seattle's streets.

By that time police had bolstered their ranks with hundreds of unarmed
National Guardsmen and Washington State Patrol troopers - the gentle approach, they said, had failed.

On balance most Americans are likely to give the police the benefit of the doubt and blame a small minority of troublemakers for sparking what is already being called the "Battle for Seattle".

But for those who had hoped to portray Seattle as an easy-going city, built on the American ideals of free speech and expression, the images of armour clad police fighting a pitched battle with unarmed protesters will be hard to erase.